The owners or occupiers of many domestic and commercial premises utilise a vacuum cleaner to clean the floors and other areas of the premises. A vacuum cleaner operates by generating an air flow through a suction head which is placed upon or against the area to be cleaned. Dirt and debris become entrained in the air flow and are thereby carried into a collector for subsequent disposal. A vacuum cleaner may be used for a full-house clean or in between full-house cleans for spillages or spot cleaning.
Most domestic vacuum cleaners fall into two broad classes. The first class is often referred to as cylinder vacuum cleaners. In cylinder vacuum cleaners the suction head is connected via a rigid extension tube to an operating handle which in turn is connected to a flexible hose through which the dirt and debris pass on their way to the collector. The collector is located within a body which also contains the motor, the body having wheels or slides by which it may be pulled across the floor during the cleaning operation.
The second class is often referred to as upright vacuum cleaners. In upright vacuum cleaners the motor and collector are carried by, or in some cases are integral with, the operating handle, so that the body containing the motor and the collector typically lie above the suction head during the cleaning operation.
The suction head of both classes of vacuum cleaner can be fitted with a rotating brush which is designed to engage and physically move dirt and debris into the suction head where it can be entrained in the air flow. Also, both classes of vacuum cleaner can incorporate a steering joint between the suction head and the operating handle, allowing the suction head to be steered in a chosen direction.
Although the suction head of a cylinder vacuum cleaner is connected to the body by way of a flexible hose and can be manoeuvred so as to allow the cleaning of walls, stairs and the like, it is uncommon to do so. Instead, the suction head and extension tubes are typically removed from the hose and replaced by a smaller upholstery tool, dusting brush, crevice tool or other cleaning tool whereby to undertake a particular cleaning operation. Such tools may be used together with an extension tube to clean locations which are high up by more diligent users.
It is not possible to manoeuvre the suction head of an upright vacuum cleaner in the same way as that of a cylinder vacuum cleaner, and in order to enable the cleaning of areas such as stairs the manufacturers of upright vacuum cleaners provide an alternative solution. Specifically, the upright vacuum cleaner is typically fitted with a length of extendable flexible hose between the suction head and the collector, the end of the hose adjacent to the suction head being releasable whereby the end of the released hose can be fitted with a cleaning tool and manoeuvred to the desired location without the user having to move the remainder of the vacuum cleaner. The flexible hose is typically made extendable so that during normal use of the vacuum cleaner the contracted hose can be stored easily and conveniently upon the body of the vacuum cleaner. When released from its stored position the hose can be extended to reach the desired location.
Once again, however, the hose is difficult to manoeuvre to the location of use, and the resilience of the hose increases the force which must be provided in order to reach less accessible locations. The force required often exceeds that required to tip over the vacuum cleaner, and it is known for an upright vacuum cleaner to fall over during periods of use of the extended hose.
In any event, the suction head of a cylinder vacuum cleaner, and the released end of the extendable flexible hose of an upright vacuum cleaner, are manoeuvrable only within the limit set by the length of the hose. It may not be possible to reach more remote locations (such as the ceiling above a flight of stairs for example) without also lifting the body of the vacuum cleaner off the floor.
Most homes have at least one mains-powered vacuum cleaner of the first or second class described above.
A third type of vacuum cleaner is a hand-held vacuum cleaner. Hand-held vacuum cleaners are typically battery-operated and are distinguished by having a carrying handle which permits the whole vacuum cleaner to be carried during use (typically by one hand), the user being able to manoeuvre the nozzle of the vacuum cleaner to the location of use. Hand-held vacuum cleaners are intended to supplement mains-powered vacuum cleaners. Conventional hand-held vacuum cleaners are suitable for use in cleaning small areas, or for removing localised debris such as might occur during the spillage of a granular product. Notwithstanding the fact that the present vacuum cleaner is also hand-held, it has little in common with the known hand-held vacuum cleaners. Specifically, the present vacuum cleaner is intended to replace the tools of a mains-powered vacuum cleaner in terms of a normal full house clean without needing to be recharged. The area which can be cleaned during a single cleaning operation with the present vacuum cleaner is therefore large, and in particular is significantly larger than the area which can be cleaned with a known hand-held vacuum cleaner before it is necessary to recharge the vacuum cleaner.
In particular, the surface area of the furniture, walls and ceiling of a typical room may be around five times the surface area of the floor. Whilst the majority of any dirt and debris present within a room will likely fall to the floor, the “above-floor” area presents a significant area to be cleaned. An upright vacuum cleaner is totally unsuited to above-floor cleaning and a cylinder vacuum cleaner is not ideally suited for such an operation. Also, the known hand-held cleaners are not well suited to cleaning the large surface areas involved. There is therefore presently no vacuum cleaner which is designed for, and which is therefore well-suited to, above-floor cleaning, for example the routine cleaning of large areas such as walls and ceilings.
The extendable flexible hoses which are conventionally used with upright vacuum cleaners have a coil spring (usually of metal) typically located between two layers of plastic. The layers of plastic are bonded together (typically by partial melting so as to form a single layer) and thereby become bound to the coil spring. The coil spring provides the resilience for the hose to return to its contracted length, and the plastic layer makes the hose airtight.
It is a feature of the extendable flexible hoses comprising a coil spring that the spring seeks to unwind as it is stretched, and similarly seeks to re-wind as it contracts. The user will typically grip the free end of the hose before it is extended, and will often be forced to reposition the grip so that the spring can unwind as the hose is extended. The force with which the coil spring seeks to unwind can be significant, and if the user attempts to resist the unwinding then parts of the hose can collapse, with the result that less air can flow therealong.
Allowing the coil spring to unwind as it is stretched it is not always desirable. If, for example, the hose is connected to a directional cleaning tool such as a crevice tool, the user will often have fitted the cleaning tool to the released end of the hose in its desired orientation with the spring contracted. When the hose is extended and the coil spring unwinds, the user will likely have to re-orient the cleaning tool.
The manufacturers of some upright vacuum cleaners have recognised this problem, and seek to overcome it by providing a rotatable joint at the free end of the hose. The cleaning tool can therefore rotate relative to the extendable hose, and can maintain the desired orientation despite the unwinding of the coil spring.
The addition of a rotatable joint represents additional manufacturing cost. Also, a rotatable joint is relatively bulky compared to the remainder of the extendable hose and the joint can become stiff over time. It is usually not desirable to increase significantly the exterior dimension of the hose, and so it is usual to provide a rotatable joint which is only slightly larger (if at all) than the cross-section of the hose. This necessarily results in the rotatable joint restricting the air flow path, and increasing the likelihood of the hose becoming blocked adjacent to the rotatable joint.
The reduction of air flow along the extendable flexible hose is particularly significant in most upright vacuum cleaners, as the rotatable joint restricts the air flow whether the hose is released or not. The reduced air flow is therefore suffered during the major proportion of the vacuum cleaner's usage during which the hose is connected to the suction head and the rotatable joint is redundant.